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annotate 3-Prolog/day1-unification.pl @ 73:74976fddd25f

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author IBBoard <dev@ibboard.co.uk>
date Sat, 03 Feb 2018 19:52:45 +0000
parents 91d02b3d74f8
children
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91d02b3d74f8 Write up "unification" code
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1 % "=" isn't assignment in Prolog, it is "unification" - finding something where
91d02b3d74f8 Write up "unification" code
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2 % both structures are identical
91d02b3d74f8 Write up "unification" code
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3 cat(lion).
91d02b3d74f8 Write up "unification" code
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4 cat(tiger).
91d02b3d74f8 Write up "unification" code
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5
91d02b3d74f8 Write up "unification" code
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6 % This rule makes sure that X, Y and Z match a lion, a tiger and a bear (oh my!)
91d02b3d74f8 Write up "unification" code
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7 dorothy(X, Y, Z) :- X = lion, Y = tiger, Z = bear.
91d02b3d74f8 Write up "unification" code
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91d02b3d74f8 Write up "unification" code
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9 % This rule checks whether both things are cats, if so then they are "twin_cats"
91d02b3d74f8 Write up "unification" code
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10 twin_cats(X, Y) :- cat(X), cat(Y).